10 Best Tankless Hot Water Heater of 2025

Tested and Reviewed: Top 10 Tankless Hot Water Heater deals with expert ratings from 8.1 to a perfect 10

June 2025 Edition

Editor's Choice

9.7

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EcoSmart

EcoSmart ECO 11 Electric Tankless Water Heater, 13KW at 240 Volts with Patented Self Modulating Technology

40% Off

Editor's bottom line:

“This tankless hot water heater is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

Endless On-Demand Hot Water; Consistent hot water when you need it that never runs out; Continuously monitored water temperature and controlled flow rates ensure efficiency and consistent performance within 1 degree of selected temperature.Amperage Draw : 54 A.Special Features: Energy Efficient
Save Space; EcoSmart tankless electric water heaters are 90% smaller than traditional tank heaters; may be installed on wall or at point of use; Dimensions 11.5 x 8 x 3.75 inches
Save Energy; EcoSmart tankless electric water heaters are 99% thermal energy efficient; Only heats water when called unlike a tank heater that maintains water temperature even when not being used.
EcoSmart ECO 11 Sizing; 13-kilowatt tankless electric water heater ideal for providing hot water for a bathroom, small sink, office breakroom and other point-of-use or low-flow applications; provides between 1.3 and 3.1 gallons-per-minute depending on the inlet water temperature; refer to the sizing guide to select the proper solution

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Picked by 279 people today

9.5

Rheem

Rheem 11kW 240V Tankless Electric Water Heater

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Main Highlights

ON/OFF Dial Control with adjustable digital temperature display
Self-modulating power control
11kW Model Flow Rate: up to 2.68 GPM
Side 1/2" NPT water connections
On demand, consistent and continuous hot water

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9.5

Save 22%

Stiebel Eltron

Stiebel Eltron 239223 Tankless Water Heater – Tempra 29 Plus – Electric, On Demand Hot Water, Eco, White, 23

22% OffFree Shipping

Main Highlights

On demand a continuous and unlimited supply of hot water
Sleek design saves space and no venting required, It also features two different temperature memory presets, making it easy to adjust for personalized needs.
Requires hard-wired 240 or 208-volt electric service, with a maximum draw of 28,800 watts at 240 volts or 21,600 watts at 208 volts
Requires 3 separate dedicated 40 amp breakers with 8 gauge copper wiring, and a minimum of 200 amp total service to the residence

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9.2

ECOTINYMACH

ECOTINYMACH 110V Tankless Water Heater Electric, 3000W Compact Water Heater Under Sink, Conveniently Convertible Between Fahrenheit and Celsius

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Main Highlights

Compact Design: ECOTINYMACH's tankless water heater is designed with a compact footprint, offering an efficient solution for heating water without consuming unnecessary space.
Convertible Temperature Scale: Unique feature of our heater allows you to switch between Fahrenheit and Celsius temperature scales conveniently, enabling you to monitor the water temperature in a scale that suits you best.
Easy Installation: Designed with simplicity in mind, our tankless water heater can be installed quickly and easily, saving you time and effort.
Electric and Energy Efficient: Being electric and tankless, this water heater from ECOTINYMACH is not only efficient but also environmentally friendly, helping you save on your energy bills and reduce your carbon footprint.
Installation instructions: Circuit breaker 32AMP, thread size: 1/2 "NPT, wire requires 2.5mm ² (13AWG).

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9.0

ECOTOUCH

Electric Tankless Water Heater, ECOTOUCH 14kW Instant Hot Water Heater on Demand 240V Point of Use Hot Water Heater ETL Certificated Self-Modulation ECO140B Black

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Main Highlights

INSTANT & SUFFICIENT HOT WATER With real powerful 14kW smart heating system, the tankless hot water heater electric ECO140B supplies sufficient instant and endless hot water of 120 or higher in seconds, no waiting for preheating nor terrible temp fluctuation during shower time any more and no worry of running out of it. Perfect companion for small apartment use, including shower, sink faucets, dishwasher, washing machine, etc.
SELF MODULATION INSTANT WATER HEATERThe electric on demand tankless hot water heater ECO140B adjusts exact power input based on current flow rate and temp setting. For example, less power will be consumed by the smart water heater when you reduce water flow, thus, you get ideal temperature instead of scalding hot, which ensures comfortable experience and excellent energy efficiency. Also, optimal energy efficiency of 98% saves considerable electric charge for you.
CONVENIENT USEThe electric tankless water heater 14kW comes with digital display & touch control panel so temp setting is easy job. Best of all, useful information on the screen helps you get full understanding of the working status of the 240V water heater tankless, you neednt go through hard lesson of setting. Now turn on the faucet and let the smart instant hot water heater do the rest.
SAFE and DURABLENewly updated and applied with multiple protections, such as leakage protection, over heating protection and auto stop,every piece electric tankless water heater ECO140B goes through strict tests to ensure 100% safety and it is listed by ETL and qualifies for UL. Inner water and electricity lines are designed to run separately so as to avoid leakage risk and scale build up. You can expect outstanding performance for years to come.
POINT of USE WATER HEATERThe sleek tankless water heater ECO140B is compact as shoes box, making it possible to install anywhere point of use to avoid waste, ideal for shower, kitchen, bar, school and hair salon. Please verify it is the right size for you: 14kW at 240V(only); dimensions 11.14" (W) x 15.87" (H) x 3.46" (D); plumbing connections :1/2" NPT. In order to install 14kW Tankless Water Heater it would requires 240 Voltage, 1X60AMP Double Pole Breaker and 1X6AWG/2 wires with Grounding.

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8.8

Save 10%

BOSCH

BOSCH Electric Mini-Tank Water Heater Tronic 3000 T 4-Gallon (ES4) - Eliminate Time for Hot Water - Shelf, Wall or Floor Mounted

10% OffFree Shipping

Main Highlights

CONVENIENT HOT WATER HEATER: 4 gallon point-of-use mini-tank fits under your sink to provide hot water right where you need it. Thermal efficiency is 98%. Dimensions : 13.75 W x 13.75 H x 13.5 D Inches
LONG LASTING QUALITY: This electric water heater is easy to maintain and has premium glass-lined material for a long service life. (Amps 12A, Volts (VAC) 120)
INDEPENDENT INSTALLATION: 36-37" cord plugs into a 120 volt outlet for independent installation or in-line with a large hot water source
FAST RECOVERY RATE: Eliminates long waits for hot water at your sink, get on demand hot water at your every need (supplies up to 2 sinks at a time)
EASILY MOUNTED: Can be shelf, wall or floor mounted (bracket included); simply tap into the cold water line and install the water heater directly at the sink to provide hot water
RETAIL DISCLAIMER FOR MINI-TANKS: Per industry standards, we recommend inspecting the anode rod annually and replacing at the first sign of degradation. Failure to replace the anode rod may cause the tank to fail and leak. Damage caused to the product, and any subsequent property damage, resulting from not maintaining the anode rod is not covered under the manufacturers warranty.

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8.6

Ranein

Ranein Propane Gas Tankless Water Heater, Indoor Max 3.6 GPM, 80,000 BTU Instant Hot Water Heater

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Main Highlights

Performance: The on-demand tankless water heater boasts a heating capacity of 80,000 BTU and a hot water flow rate of 3.6 gallons per minute (GPM). It can provide continuous hot water for 2-3 water supply points, making it sufficient to meet the hot water needs of a household's bathroom, kitchen, and bar area.
No Waiting Required: Unlike traditional tank water heaters, tankless water heaters eliminate the need for a 30-minute preheating wait time, allowing you to have unlimited hot water on demand.
Provides 4 modes: Dish mode(100), Fruit mode(95), Elderly mode(104) and Infant mode(107). More convenient for you to use.
Save Money: The kit already includes the exhaust pipe, so you don't need to spend extra money on purchasing it separately. With an oxygen-free copper water tank, it reduces heat loss and lowers energy consumption. Applied with standard 1/2" NPT water fitting and gas inlet.
Recommendation: We strongly advise that all installations of the device adhere to local building and plumbing regulations at the installation location, and should be carried out by licensed professionals.(Not recommended for areas over 2,000 feet)

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8.3

Save 6%

Rheem

Rheem 18kW 240V Tankless Electric Water Heater, Gray

6% Off

Main Highlights

External digital thermostatic control with LED display (+/1 degree accuracy)
Most advanced self-modulation, adjust power to meet hot water demand
Durable Copper immersion two heating elements, field Serviceable. Flow Rate- up to 4.4 GPM
Simple installation bottom 3/4 inch NPT water connections
Threaded for easy replacement, simple installation, digital temperature display

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8.1

Save 20%

Rheem

Rheem RTG-95DVLN-3 High Efficiency Non-Condensing Indoor Tankless Natural Gas Water Heater, 9.5 GPM

20% OffFree Shipping

Main Highlights

Continuous Hot Water & Comfort When Needed Provides enough hot water for your entire house, even when using multiple applications such as a shower and dishwasher
Save on Energy Costs High Efficient Water Heater only runs when needed
Save Water Water Saving Setting saves up to 1,100 gallons of water per year
Hot-start programming keeps the water heater in a ready state, avoiding any cold-water bursts
Leak Protection LeakGuard Leak Detection & Prevention protects your home from water damage that detects any internal leak, both large or small

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8.1

Save 10%

Rinnai

NEW Rinnai RXP199iN Condensing Smart Sense Natural Gas or Propane Tankless Water Heater, Indoor or Outdoor Water Heater, Up to 11.1 GPM, 199,000 BTU

10% OffFree Shipping

Main Highlights

One Model, Anywhere: This Rinnai tankless water heater is installable indoors or outdoors thanks to our new Versa Vent and powered by either propane or natural gas thanks to a Smart Sense gas control system; RX-OVC vent cap required for outdoor install
Never Run Out of Hot Water with this Compact Tankless Gas Water Heater: This condensing propane and natural gas tankless water heater from Rinnai is only the size of a small suitcase, but provides up to 11.1 GPM (7 fixtures at once)
Smart, Efficient Design: This water heater's modern design includes an easy-to-use interface, Quick Flush feature for simplified flushing, as well as a super-high energy efficiency factor of UEF .98; See Controlr module for WiFi control (not included)
Smart-Circ Intelligent Recirculation: This tankless hot water heater includes an internal pump and features Smart-Circ technology that learns your water usage patterns, then schedules pump and recirculation accordingly for best efficiency and convenience
Professional Installation Recommended: Visit the Find a Rinnai PRO page on our website to find a qualified technician to install your tankless water heater, and use the Rinnai Central App for help with setup, service & troubleshooting; We do not recommend installing a water heater without a technician

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Our Best Overall Choice

Best Choice

9.7

EcoSmart

EcoSmart ECO 11 Electric Tankless Water Heater, 13KW at 240 Volts with Patented Self Modulating Technology

40% Off

Editor's bottom line:

“This is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

Endless On-Demand Hot Water; Consistent hot water when you need it that never runs out; Continuously monitored water temperature and controlled flow rates ensure efficiency and consistent performance within 1 degree of selected temperature.Amperage Draw : 54 A.Special Features: Energy Efficient
Save Space; EcoSmart tankless electric water heaters are 90% smaller than traditional tank heaters; may be installed on wall or at point of use; Dimensions 11.5 x 8 x 3.75 inches
Save Energy; EcoSmart tankless electric water heaters are 99% thermal energy efficient; Only heats water when called unlike a tank heater that maintains water temperature even when not being used.
EcoSmart ECO 11 Sizing; 13-kilowatt tankless electric water heater ideal for providing hot water for a bathroom, small sink, office breakroom and other point-of-use or low-flow applications; provides between 1.3 and 3.1 gallons-per-minute depending on the inlet water temperature; refer to the sizing guide to select the proper solution

Show Price